I don't know more about it and I haven't read his book, but I do see that he's considered a contrarian in the field.

Although I tended to be a believer when I was much younger, experience with h.sapiens and a lot of reading makes me VERY skeptical of any claims of "nonviolent society" (unless they were the ONLY society in the area) and "matriarchal societies" and "living in harmony with the earth" (easy to do if there's only a few hundred of you. NOT easy if there's a billion or so.) I'm not as suspicious of "egalitarian societies" as we've seen some examples of those.

-- Byrd
Moderator, Hall of Ma'at